Maximum Profit from House Prices

You are given an array of integers representing the price of a house on different days. Your task is to determine the maximum profit achievable by buying the house on one day and selling it on a later day. Formally, given an array P of length n, you need to compute:

$$\max_{0 \leq i < j < n}\left(P[j]-P[i]\right)$$

If no profit can be made, output 0.

Note: The selling day must come after the buying day.

inputFormat

The input is read from stdin and consists of:

• An integer n on the first line representing the number of days.
• A line with n space-separated integers where the i-th integer is the price of the house on the i-th day.

outputFormat

Output a single integer to stdout representing the maximum profit that can be achieved by buying and selling the house.

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